1) Is it aerodynamically feasable to fire a golf ball from a direct injection propane combustion 'spud' gun (metalloid barrel and chamber, of course... this is out of PVC league) at speeds in excess of 2800 ft/s (720m/h, ~320m/s, mach 1)?
2) If it is feasable, what would be the optimal barrel length, chamber volume, chamber:barrel ratio, and build material for said supersonic speeds; does the phrase 'bigger is better' apply here, or does efficiency drop off after a certain size?
3) Have there been any previous attempts/successes at supersonic speeds in the history of direct injection propane, (no hybrids, oxy-acetyline mess... straight propane.) and, if there have been, could you provide a link?
4) Given the previous three are true, Is it possible to reach mach 2 by any means, hybrid, and what not?
Eventually, we just start looking at a slug fired out of a shotgun of sorts; except without black powder. And much more illegal. 8)
If we can actually create and compile a comprehensive thread with all the data in it, we might be able to build a few DIY supersonic 'spud' guns. Which would be awesome.
Golf balls would make ideal projectiles for this, but i'm sure racketballs would work... tennis balls have too much fuzz and would probably warp to an odd un-aerodynamic shape. Hence, coefficient of drag would be too high at peak for supersonic speeds to be substantiated long enough to be significant.
Oh. And, I've used tfse. However, to no avail. I research before I post, unlike some people...
Cheers.
Mike.
